Recently, there has been a growing consensus that global warming and resultant climatic change are serious threats to future socioeconomic stability. This has prompted interest in carbon capture and storage—so-called “carbon sequestration”—as a way of continuing to use fossil fuels without releasing carbon dioxide into the atmosphere. Unfortunately, carbon capture and sequestration technologies are not yet fully developed. Furthermore, designing power plants to capture the carbon they produce is likely to reduce their efficiency substantially. Consequently, most fossil-fuelled power-plants are still being built without provision for future carbon capture. It is therefore likely that governments will make regulations and/or provide incentives so that plants are designed for ease of retrofitting with carbon-capture equipment; i.e., they will be designed so that they are “carbon-capture ready”.
Hitherto, steam turbines for power plants have normally been built to operate for their entire life on a particular thermodynamic cycle, as shown in German patent no. DE 628 830 C. However, depending on the carbon capture measures adopted, retrofitting of power plants with carbon capture equipment will necessitate modification of their steam turbines. An object of the present invention is therefore to provide steam turbines that are readily modifiable after design and manufacture to accommodate, at minimum expense, the demands of carbon-capture equipment added to the power generation plant at a later date.